'The Big Rip:' Here's What it Could Mean if the Universe is Tearing Itself Apart

After introducing his theory of general relativity in 1915 and turning the scientific world on its head, Albert Einstein wasn't happy. According to the math of his theory, the universe had to be constantly expanding or contracting, but neither prospect appealed to Einstein. To "fix" this problem, he published a paper in 1917 proposing the existence of a "cosmological constant," some force that would keep the universe's boundaries static and unchanging. After being proven wrong by Edwin Hubble, who discovered the universe really was expanding, Einstein called it his "greatest mistake," but even Einstein couldn't have counted on what astronomers and astrophysicists would discover in 1998: the universe's expansion was accelerating.

The force driving this expansion has long been proposed to be dark energy, which is estimated to make up about 68% of all energy in the universe. What's strange about dark energy is that even though it's causing the boundaries of the universe to expand, causing matter, radiation, and other forms of energy to become more spread out, dark energy itself doesn't seem to be diluted by this—its density across the universe seems to stay constant. This is an interesting phenomenon, because if dark energy really is constant, then the universe will continue to expand indefinitely. If it's not constant, one of three scenarios will occur: 1) the universe will stop expanding, 2) the universe will start contracting and collapse on itself (the so-called 'Big Crunch'), or 3) the universe keep expanding at a faster and faster rate, until everything rips itself apart, ending in a 'Big Rip.'

Right now, the expansion of the universe is already increasing the distances between galaxies by a very small amount, which has led scientists to propose that any advanced civilization will eventually have to start collecting stars or begin a mass migration to galaxy clusters in order to avoid becoming stranded in the void. However, if dark energy is pouring gasoline on the rate of expansion, then the all life (and matter) is doomed: the universe will continue to stretch until galaxies are torn apart, then solar systems, then planets, all the way to atoms, until space-time itself is ripped apart.

However, if this is our fate, it won't come for a while. According to Ethan Siegel, a Forbes columnist: "If the Universe will end in a Big Rip, that's a fate that won't befall us until 80 billion years from now at the earliest: nearly six times the present age of the Universe. The unbinding of galaxies from one another, the very first notable step on the path to a Big Rip, won't occur for many tens of billions of years even in the most pessimistic viable scenario."

80 billion years? That's a pretty good run for a universe.

Explore the other wonders of our universe by opening this infographic: